Non-magnetic watch-balance



(No Model.)

G. F. CARPENTER, NON MAGNETIC WATCH BALANCE.

No. 489,790. Patented Jan. 10, 1893.

A I WM v 4 Cation/w,

UNirEn Sterne PATENT Enron,

CHARLES E. CARPENTER, OF LOUISVILLE, KENTUCKY.

NON-MAGNETEC WATCH-BALANCE.

SPECIFICATION forming part of Letters Patent No. 489,790, dated anuary10, 1893.

.. Application filed February 29,1892. Serial No. 423,245. (No model.)

To all whom it may concern:

Be it known that I, CHARLES F. CARPENTER, a citizen of the UnitedStates, and a resident of Louisville, in the county of Jefferson andState of Kentucky, have invented certain new and useful Improvements inatches and other Time-Keeping Instruments; and I do declare thefollowing to be a full, clear, and exact description of theinvention,such as will enable others skilled in the art to which it appertains tomake and use the same, reference being had to the accompanying drawing,and to letters of reference marked thereon, which form a part of thisspecification.

The figure of the drawing is a representation of the invention and is aplan view.

The invention has relation to certain new and useful improvements incompensating balances, and balance springs, for watches, chron'ometersand other like instruments; and it consists in the novel constructionand combination of parts as hereinafter specified.

The balance springs and balances in watches, chronometers the. arecominonlymade of steel, but this metal is now objectionable for thatpurpose because steel is acted upon by electricity and magnetism, andconsequently the time keeping qualities of watches and chronometers areseriously injured thereby.

The ordinary compensating balance in a watch, chronometer etc. has tworims in each segment, the inner rim A, A and arm C of steel, the outerrim 13,13 of brass, the unequal expansion of which two metals indifferent degrees of temperature is just enough to move the screws orweights D, D, D, D, D, D',the proper distance toward and from the centerof the balance to compensate for the changes produced in a steel balancespring by the same variations of temperature; but a balance and springso constructed are acted upon by electricity and magnetism andconsequently keep very irregular time.

A watch, chronometer due. with an ordinary steel balance spring, and aplain or non-com- 90 Fahrenheit. When a proper relation of the balanceand balance spring is established by compensation, the variation causedby clifferent degrees of temperature is hardly appreciable. The balanceand balance spring mutually compensate for each other in cor rect timekeeping. To render a watch, chronometer ozc. free from magneticinfluences it must have a non-magnetic balance and a nonmagnetic balancespring.

I construct my non-magnetic balance in the following manner. The innerrim A, A and arm C are constructed of silicon bronze, the outer rim B, Bis made of CEtCllllllll'll (fifty to sixty parts) and silver (forty tofifty parts). The balance spring E, is constructed preferably ofiridio-platinum, which is not only non-magnetic, but is especiallyadapted by virtue of its other properties (as will be set forth in afuture application) for the purpose. A spring constructed of thismaterial is also found to be peculiarly effective with the balance abovedescribed.

Having described this invention, what I claim as new and desire tosecure by Letters Patent is:

1. In an instrument for keeping time, a non-magnetic compensatingbalance having its inner rim and arm of silicon bronze, and its outerrim of cadmium alloyed with silver, substantially as specified.

2. A Watch or like instrument, having, a non-magnetic balance, and anon-magnetic balance spring, substantially as specified.

3. In an instrument for keeping time, the combination with a bi-metalliccompensating balance, having one of its rims constructed from siliconbronze, and the other rim from cadmium alloyed with silver, of a balancespring of non-magnetic material, substantially as specified.

In testimony whereof I affix my signature in presence of two witnesses.

CHARLES F. CARPENTER.

Witnesses:

HARRY STUCKY, JOHN B. ENRIGHT.

